Firearm recoil buffer

ABSTRACT

A buffer for a firearm may include a piston and housing, along with an internal spring and force absorbing materials to reduce damage and wear on a buffer, allowing safe use of a wide range of loads in a firearm, or in the case of some high-power firearms such as 0.308 Win AR variants, providing additional durability to the buffer.

PRIORITY

This application claims priority to U.S. Provisional Patent Application No. 62/050,779 filed on Sep. 16, 2014, which in incorporated herein by reference in its entirety.

FIELD

This application relates generally to firearms. In particular, this application relates to recoil buffers in semi-automatic rifles.

BACKGROUND

Many firearms, particularly automatic or semi-automatic firearms use buffers to diffuse the force of moving portions of firearms to reduce and control recoil when the firearm cycles to automatically load a cartridge after firing a previous cartridge. Variations in the powder loads of different cartridges and other ballistic differences may cause variations in the amount of force of recoil, and consequently, the force a buffer may experience, sometimes leading to failure or premature wear of the buffer.

Current buffer systems each have significant drawbacks and are not adjustable for different applications. For example some buffer systems include:

Passive Buffers: Use different weight, which only address premature unlocking, but increase reciprocating mass, which is harder on the primary buffer springs, increases felt recoil, gun movement and carrier bounce.

Hydraulic Buffers: Use hydraulic filled buffers with pistons that have set valve rates and fluid weights. These are not adjustable for either weight or dampening and have a number of shortcomings. As the rate of fire increases the dampening increases as the system stiffens and buffering effect is reduced as the hydraulic system adopts an almost solid, rigid state. This permits carrier bounce, and velocity increases. These systems also fail as seals blow under hard use. Dampening can also be effected by extreme hot or cold temperatures, which can change the way the system functions and lead to improper or malfunctioning weapons.

Energy Absorbing Buffers: These use some energy absorbing material with either a movable head or bumper/base that acts against the energy absorbing material, which helps to reduce carrier bounce and to some degree carrier velocity. They are non-configurable for either weight or dampening/rebound.

Pneumatic Buffers: Are not very common and are expensive. They are similar to hydraulic buffers but use compressed air and valves to provide a recoil dampening effect. They are not configurable for weight and only moderately configurable for dampening via air pressure.

SUMMARY

A buffer for a firearm may include a piston and housing, along with an internal spring and force absorbing materials to reduce damage and wear on a buffer, allowing safe use of a wide range of loads in a firearm, or in the case of some high-power firearms such as 0.308 Win AR variants, providing additional durability to the buffer.

BRIEF DESCRIPTION OF THE DRAWINGS

The following description can be better understood in light of Figures, in which:

FIGS. 1 illustrates a cross-sectional view of an exemplary firearm buffer; and

FIGS. 2a-3b illustrate individual components of exemplary firearm buffers.

Together with the following description, the Figures demonstrate and explain the principles of the firearm buffer. In the Figures, the thickness and configuration of components may be exaggerated for clarity. The same reference numerals in different Figures represent the same component.

DETAILED DESCRIPTION

The following description supplies specific details in order to provide a thorough understanding. Nevertheless, the skilled artisan would understand that the apparatus and associated methods of using the apparatus can be implemented and used without employing these specific details. Indeed, the apparatus and associated methods can be placed into practice by modifying the illustrated apparatus and associated methods and can be used in conjunction with any other apparatus and techniques conventionally used in the industry. For example, although the exemplary buffers shown in the Figures and described below are generally for the AR-15/M4/M16/AR-10 platform and mechanism, the principles and solutions provided and described with respect to the exemplary embodiments may be applied to other buffers for other firearms systems.

Generally, the majority of many automatic or semi-automatic rifles, such as AR-15/M4 and AR-10/AR-308 platform rifles and carbines are typically “over gassed” and “under sprung” which yields poor function, degrades performance and accuracy and shortens component and rifle service life. The over gassing and under springing results from designs that allow for the greatest range of ammunition to be fired from the rifle. An over gassed rifle allows for cycling and reloading with a low power/low powder load such that the pressure wave is sufficient to unlock the bolt and allow the cycling. Similarly, an under sprung rifle includes a recoil spring that allows the buffer to slam into buffer tube, instead of a properly selected spring that would allow the bolt to cycle without slamming the buffer into the end of the buffer tube and completely compressing the spring. The majority of AR platform rifle and barrel manufacturers deliberately over gas and under spring their rifles, so that they will run, albeit poorly, with the widest range of possible ammunition and conditions and to minimize support calls. In addition, the timing on M4 and carbine length gas system variants is also not ideal and further exacerbates the problems with premature unlocking of the bolt, premature extraction of the case, and incomplete powder burn causing reliability and performance issues.

Over gassing leads to excessive bolt carrier velocity, this causes several issues. First, it causes fired cases to impact the shell deflector on the upper receiver and cases can be deflected back into the ejection port causing jams. Second, it causes “carrier bounce” where the bolt carrier and buffer slam back hard into the end of the buffer tube. This causes several issues, more felt recoil, erratic feeding from the magazine, causing jams, and occasionally reverse bounce where the bolt and carrier bounce slightly “out of battery” which can lead to an out of battery detonation. Faster bolt carrier speed can also lead to premature extractor spring failure and as the spring is kept in the “open” state longer, and extractor failure as extractors are not properly engaging and feeding cartridges from the magazine.

Poor timing is typically due to the higher pressure peak and curve and shorter gas tube length on carbine length gas systems, along with oversize gas ports. Weak recoil/buffer springs exacerbate the timing problems. With poor timing the bolt begins to unlock while the system is still under high heat and pressure with bullet is still in the barrel and cartridge case walls have not released from the chamber walls. This leads to extractor breakage, extractor spring failure, bolt lug breakage, and cartridge case separation. It also creates “blow back” through the chamber of hot gasses, unburnt powder and burnt carbon into the action, which causes a number of reliability issues.

The active buffer systems shown in the Figures and described below can be configured for various spring rate and buffer weights. This allows the user to tune their AR platform rifle or carbine, via the use of a range of secondary buffer springs to augment the primary spring, which may slow bolt carrier speed and eliminates carrier bounce. Through using different rate springs within the exemplary buffers, users may achieve the proper amount of buffering for their individual setup. Additionally, exemplary buffers may include different energy absorbing materials and components which may help to absorb recoil energy, dampen accuracy robbing vibration and assure the elimination of bolt carrier bounce under high rate of fire applications. Through its modular, configurable design, the exemplary buffer systems shown in the Figures and described below in detail may allow the use of different weight components that can add or reduce the weight to the reciprocating mass of the bolt carrier/buffer combination. More weight is helpful with poorly timed carbine or pistol length gas system configurations.

By increasing the weight within the buffer, bolt unlocking may be delayed, allowing pressures to drop and some poor timing issues to be reduced. Lighter carrier and buffer weight combinations may help to lower reciprocating mass energy and thus reduce felt recoil and gun movement, which allows faster, more accurate follow-up shots. However, this lower weight also leads to higher carrier velocity, which exacerbates feeding issues and carrier bounce. The exemplary buffer systems may allow the use of light weight components in the buffer to reduce reciprocating mass, but also allow the user to control that lower mass and reduce the resultant higher carrier velocity by using the proper secondary spring, along with the energy absorbing components and materials.

Turning now to the Figures, buffer 100 may include body 110, piston 120, head 130, spring 140, bumper 150, and damper disk 170. As shown in the Figures, body 110 may include vent port 112, an open end to receive head 130 in a removable relationship with interface 132, and a necked end 114 with a hole to accommodate a portion of piston 120 to extend therefrom. Body 110 may be made from a material selected depending on the desired configuration. For example, 303, 304 or 17/4 Stainless Steel or similar may be used for general use with most rifle set ups, 7075-T6 Aluminum may be used for a lightweight configuration, Tungsten or tungsten alloys for heavy configurations, and titanium or titanium alloys for high power lightweight configurations. Of course any other material suitable to withstand the stresses and strains may be used based on desired mass, as described above.

In some embodiments, head 130 may be formed with an interface 132, for example threads, to removably attach to body 110. Head 130 is positioned in the rifle to interface with an end of a bolt carrier group. Head 130 may be formed using the same materials as described above with respect to body 110. Head 130 and body 110 always reciprocate within a buffer tube of the rifle such that proper selection of the mass of the head and body may be used to affect a desired travel speed of the bolt carrier group and the buffer.

Piston 120 may include seat 122 for engaging spring 140 and neck 114 of body 114. When head 130 and body 110 are coupled together, seat 122 and a lower portion of piston 120 are constrained within body 110. The lower portion may extend within the center of spring 140 to keep the spring from compressing completely and possibly failing prematurely. Similarly, the lower portion may provide stability to spring when in use.

Piston 120 may be formed of various materials for different uses, for example an ultra-high density co-polymer, such as Delrin® may be used to form piston 120 to absorb energy. Similarly, stainless steel, Aluminum or Al alloys, Tungsten or Titanium, similar to those identified above, may also be used to provide a desired overall mass of buffer 100 as desired.

Spring 140 may be selected depending on the amount of force for the setup of the rifle and ammunition selected for additional recoil reduction and smoothing the cycling of the rifle. Changing the spring may be the primary way of adjusting the buffering provided by buffer 100 for different gun set-ups or selected ammunition. Spring 140 may be formed from Chrome Silicon steel with varying diameters and gauges for different spring rates. Other materials may also be appropriate.

Bumper 150 extends into the buffer tube and would impact the end of the buffer tube of a rifle when the rifle recoils in most applications. Bumper 150 may be formed with a domed configuration to further provide progressive dampening and energy absorption as bumper 150 compresses upon contact as opposed to a flat end with uniform dampening and deformation. Bumper 150 may be formed from Sorbothane® or any other suitable energy absorbing material. Bumper 150 may be attached to an end of piston 120 with washer 154 and pin 152, which may be formed of any suitable material, such as steel, aluminum, etc.

Damper disk 170 may provide a similar function as bumper 150 in absorbing and dampening the recoil forces. Damper disk may be positioned between head 130 and spring 140, as shown in the Figures. Damper disk 170 may be formed of an energy absorbing material such as WonderBuff® polymer energy absorbing material, or any other suitable material.

Each of the components may be coated with a coating to provide additional friction and wear reduction, as well as resisting carbon penetration during normal use. For example, each metal component may be coated with an H-Series Cerakote® (reduces friction, eliminates corrosion, carbon and dirt etc., won't adhere, highly chemical resistant, provides color coding of components and color customization for differing applications)

Buffer 100 may provide significant advantages in various circumstances. For example, advantages may include:

Reliability: Weapons reliability is paramount in virtually every intended application. AR reliability is directly affected by poor timing and being over gassed. Principal among these are, with the direct gas impingement operating system, they run dirty, are more prone to feeding and ejection related malfunctions, broken extractors, extractor spring failures, broken bolts, and premature buffer spring failures. Proper timing mitigates or eliminates all of these maladies.

Tactical—Military and Police: Properly timed and tuned AR's have been able to run for 5,000 to 15,000 rounds without cleaning or malfunctions, which is important to police and military. In addition, faster and more accurate follow up shots are possible as there is less movement of the AR.

Competition: For 3-Gun and other competitions, rapid, accurate shots are required and fractions of a second count. This is where the reduced reciprocating mass of super lightweight low mass bolt carriers and light weight buffers can benefit. However, this can lead to excessive carrier velocity and carrier bounce, which negatively affect reliability. The RCT configurable active buffer system can be configured to reduce the buffer weight, but make compensation for that reduced weight with more powerful secondary springs to keep carrier velocity at optimal rates, while the energy absorbing bumper and disc dampen vibrations that can effect accuracy and further act to mitigate carrier bounce.

Some features and benefits of buffer 100 may include: Manage Bolt Carrier Velocity, Reduce or Eliminate Bolt Carrier Bounce, Configure Buffer Weight to Match System Requirements, Reduce Felt Recoil, Reduce Vibration from Recoil System, Reduce Buffer Spring Noise, Increase Reliability and Component Life, User Configurable for secondary buffer dampening, User Configurable for buffer weight, Energy absorbing materials provide a third level of dampening and reduce vibration and noise, Works with all AR platform rifles, carbines and pistols.

Of course, any suitable material may be used for the components listed above in addition to the specifically listed materials. In some embodiments, the piston may be located on the base end of the body rather than on the bumper end as shown in the Figures, such that the bumper may be directly attached to the body and the piston end may engage with the end of a buffer tube of a firearm. In some embodiments, an energy absorbing wafer or washer may be placed between the active buffer and the end of the buffer tube to protect both the buffer tube and the buffer.

In addition to any previously indicated modification, numerous other variations and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of this description, and appended claims are intended to cover such modifications and arrangements. Thus, while the information has been described above with particularity and detail in connection with what is presently deemed to be the most practical and preferred aspects, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, form, function, manner of operation and use may be made without departing from the principles and concepts set forth herein. Also, as used herein, examples are meant to be illustrative only and should not be construed to be limiting in any manner. 

1. An active firearm buffer, the buffer comprising: a body; a piston slidably positioned within the body; a biasing mechanism configured to bias the piston to an extended position such that an end of the piston extends from the body; and a bumper configured to contact a moving portion of a firearm when the firearm is fired. 